In POS (Point Of Sales) terminals installed in settlement places (checkout counters: cash registers) of supermarkets, mass merchandising stores, and the like, a salesclerk enters data of commodities with barcodes attached thereto by using a barcode input device and enters data of commodities to which barcodes cannot be attached by using a keyboard. Therefore, the time necessary for entering data of commodities with no barcodes attached thereto widely changes depending on the level of the skill of the salesclerk. In some cases, a salesclerk attaches store-original barcodes to commodities with no barcodes attached thereto in advance. However, such a task leads to an increase in working hours. Meanwhile, recently, self-checkout counters in which a customer operates a POS terminal device by himself/herself have been increasing. Since it takes time for a customer to find where a barcode is attached to a commodity, the time necessary for operating the POS terminal device further increases.
Therefore, a technique for taking an image (i.e., a picture) of a commodity by using a camera or the like disposed inside a POS terminal device and recognizing the commodity by using an image recognition technique has been proposed. For example, Patent Literature 1 discloses an apparatus that captures a frame image including an image of an object taken by image pickup means and performs an object recognition process by using the captured frame image. The apparatus disclosed in Patent Literature 1 captures a frame image including an image of an object taken by the image pickup means, and lowers a reference value when a color attribute of the captured frame image does not exceed the reference value and performs the object recognition process when the color attribute of the captured frame image exceeds the reference value.